Is the DualSun SPRING panel drainback compatible?
Edited
Yes, the DualSun SPRING panel is drainback compatible!
SPRING4
Even if we don’t recommend it, SPRING4 panels are compatible with an auto drain back system.
SPRING3
In portrait mode SPRING3 are auto drainning as per our direct pool heating system. But as the Dualsun SPRING links are supple it can create low point where water can be trapped
>To go further : What material is used for the SPRING panel heat exchanger?